Grey Dagger

73.038 (2284) Grey DaggerAcronicta psi (Linnaeus, 1758)

Status

Resident. Local.

UK BAP Priority Species.

Flight period

J

F

M

A

M

J

J

A

S

O

N

D

█

█

█

█

█

█

█

█

█

History

Lennon (1863) stated it was common everywhere. Douglas Robinson (1870-71) had found a few at sugar in July on Almorness (VC73). He also found the larvae abundant in July and August. Gordon (1913) stated it to be common and generally distributed; eight having been seen on one treacle patch at midnight 29th June 1905 at Corsemalzie, Wigtownshire.

Sir Arthur Duncan (1909-84) during his lifetime had found it at Closeburn, Tynron and Castlehill, Dumfries (all VC72). Archibald Russell (1944) listed it as occurring near Gatehouse of Fleet (VC73) during the years 1942-43.

The 1970s produced 20 records with a dip during the 1980s to 12 records, followed by a peak during the 1990s of 77, and during the first decade of the 21st century, a very similar level of 70 records. All were from widely scattered sites across the region.

Life cycle

One generation. Overwinters as a pupa. Larvae are present late July to early October and are quite distinct from Dark Dagger larvae, and are easy to rear.

Larval foodplants

Apple, Blackthorn, hawthorns, birches, limes and elms to name a few.

Identification

The genitalia will need to be examined for determination from Dark Dagger which has now appeared in Scotland.

Habitat

Many habitats, but mainly woodland.

Recorders' notes

Take a minimum of specimens from any one site for genitalia determination.